The reading scheme of the existing contactless IC card reader is sending data based on communication protocols such as 14443 and 15693. According to the above protocols, a frame waiting time (FWT) exists after the reader sends instruction data, which indicates a maximum time range for the card reader to wait to receive response data. That is, after the card reader sends an instruction to a card, the card reader waits to receive the response data of the card, and the card reader considers the returned data to be legal as long as the data is returned within the frame waiting time (FWT). According to the above communication protocols, if a third party intercepts the data sent by the card reader and returns the response data within the FWT time, the card reader will consider the source of the data to be reliable. Thus, it can be seen that the solution has security risks, such as being attacked by a third party or data being altered.